NEW YORK (Reuters) - The graceful mute swan, in lore long associated with romance and fidelity, might not meet a fairy tale ending in New York.

The state is planning to eliminate by 2025 the entire population of the regal wild mute swans, which its Department of Environmental Conservation calls an aggressive, invasive species and a danger to people and native wildlife populations.

But protests are mounting to block the plan that would use tactics such as shooting the birds and puncturing their eggs.

"It's a ludicrous plan," said David Karopkin, founder and director of GooseWatch NYC, a wildlife advocacy group that said the state's concerns are overblown.

Most of the state's 2,200 mute swans - both wild and in captivity - are found in highly populated areas, in and around New York City and its northern suburbs in the Hudson Valley.

"When people live close to each other, conflicts are inevitable, but we don't kill each other off. But when people live next to animals and conflicts are inevitable, we respond with lethal methods," Karopkin said.

Although the swans are known to be territorial, especially when protecting their eggs or their young, there are no known attacks on humans in New York, Karopkin said.

The state did not immediately respond to a request for comment on any mute swan attacks reported in New York.

Like the population control plans for mute swans already enacted in Michigan, Maryland and Delaware, the New York proposal targets only birds in the wild, not the ones on private lands or in city parks.

Originally brought in from Europe in the late 1800s to add flair to American estates, mute swans are now consuming large amounts of aquatic vegetation needed by native waterfowl and contaminating the water with their feces, which can contain the bacteria E.Coli, state wildlife experts said.

"With mute swans, there is considerable concern about destruction to native habitat by this non-native species," said wildlife expert Dr. Paul Curtis, who works in the Department of Natural Resources at Cornell University.

The mute swan's steadily increasing population in New York over several decades has put a strain on native species like the black tern, an endangered wetlands bird that has now disappeared where the swans have colonized, he said.

"I think people have sort of a romantic connection with swans...But they need to be managed responsibly," Curtis said.

This week marked a final chance for the public to comment on the state's draft plan to control the wild swan population employing methods such as "oiling, puncturing, shaking, freezing, replacing or removing eggs; destruction of nests; sterilization of birds; shooting; and capture and removal of swans to be euthanized or turned over to persons licensed to keep the birds in captivity."

GooseWatch NYC said it has collected 20,000 signatures on an online petition to scrap the proposal. State Senator Tony Avella of Queens has introduced a bill that would put a two-year moratorium on any elimination efforts.

"I was horrified to learn that our state wildlife agency would make such an extreme, unfounded proposal, and do not believe that the DEC has provided evidence to justify the elimination of these beautiful swans," Avella said.

The black-masked, white bird's body typically measures between 50 to 60 inches in length, with wingspan reaching up to 90 inches. Despite their name, mute swans are capable of making hissing, grunting and snorting sounds, although they don't honk like other swans.

Over the past century, mute swans have become a symbol of love. The birds mate for life, and when two mute swans sit beak to beak, the curve of their long necks make a heart-shape.

Animal advocates like Karopkin said there has been little proof the swans are damaging the environment.

"Non-native does not equal invasive," he said.

"There are many examples of wildlife in North America that were brought here from other continents that have been successful. It's a subjective decision that the harm is outweighing the benefit the animals provide," Karopkin said.

But to wildlife experts like Professor Curtis, the mute swans pose the same kind of danger to the natural habitat as other non-native species, including the notorious snakehead fish, a predator native to rivers and lakes in Asia and a dangerous, invasive species in American waters.

"It's a fair comparison," Curtis said. "Because both snakehead fish and swans are invasive, exotic species. Both have potential detrimental impacts on the environment and so I think both federal and state government agencies want to minimize the impacts of invasive species, whether insects or birds."